Field of the Invention
The present invention relates to a liquid jet head and a liquid jet recording device.
Background Art
There exists an inkjet printer equipped with an inkjet head as a device for ejecting ink (liquid) in a droplet state to a recording target medium (e.g., recording paper) to thereby record information (e.g., images and characters) on the recording target medium.
The inkjet head described above has an actuator block and a nozzle plate (a jet hole plate), wherein the actuator block is provided with a drive actuator for applying a fluid pressure variation to the ink having fed from a pump, and the nozzle plate is bonded to the actuator block and has jet holes communicated with the drive actuator. In the inkjet head, the ink is jetted outside through the jet holes due to the application of the pressure variation by the drive actuator.
In the case of the inkjet head of this type, the ink jetted from the jet hole forms an ink column (liquid column) having a columnar shape, and then forms an ink droplet having a predetermined volume due to the surface tension, and then lands on the recording target medium.
However, depending on the viscosity of the ink to be used, and the jet speed of the ink, the length of the ink column actually formed when being jetted from the jet hole is elongated, and a part of the ink column is separated from a main droplet and scattered around as a satellite droplet. In this case, the satellite droplet adheres to the nozzle plate or the recording target medium, and is apt to cause dirt on the nozzle plate and deterioration of the print image quality.
As the inkjet head for dealing with the above, there have been worked out an inkjet head in which it is arranged that a gas is jetted to the outside of the jet hole of the nozzle plate from a direction perpendicular to the jet direction to thereby cut off the ink column (see, e.g., Japanese Patent No. 5,047,958), an inkjet head in which it is arranged that an ultrasonic application device is disposed outside the jet hole of the nozzle plate to cut off the ink column with an ultrasonic wave, and so on.
However, in the inkjet heads described above, since a mechanism for cutting off the ink liquid column is disposed outside the jet hole, the jet hole itself is located at the position recessed from the end surface of the inkjet head, and the maintenance of the jet hole part for keeping an appropriate print quality becomes hard.
Therefore, the invention is for providing a liquid jet head and a liquid jet recording device each capable of appropriately cutting off the liquid column formed immediately after being jetted from the jet hole to prevent the satellite droplet from generating, and further achieving easier maintenance of the jet hole part.